Mercury gauge



AugQ 24, 1954 GRAYUM 2,681042 MERCURY GAUGE Filed May 9, 1952 2'INVENTOR. JO/INCUMGV4'RAYUIY Patented Aug. 24, 1954 UNITED STATES PATENTOFFICE MERCURY GAUGE John C. Grayum, Houston, Tex. Application May 9,1952, Serial No. 286,950

1 Claim. 1

The present invention relates to improvements in mercury gauges and theprincipal object is to provide a gauge of this type especially adaptedfor use in finding leaks in gas and air lines.

Another important object of the invention is to provide a mercury gaugefor the purpose stated which includes novel mercury trap means, thepurpose of which is to prevent the spilling of mercury when the gauge isnot in use.

The present application is predicated on abandoned application SerialNo. 2,770, filed on January 16, 1948, and allowed on March 1, 1950.

Other objects and advantages of the inven tion will become apparent tothe reader of the following description.

In the drawing:

Figure 1 is a fragmentary side elevational view showing part of thegauge in vertical section.

Figure 2 is a fragmentary enlarged sectional view taken on line 2-2 ofFigure 1.

Figure 3 is a fragmentary sectional and side elevational view showingthe gauge tilted and the trap valve in opened position.

Referring to the drawings wherein like numerals designate like parts, itcan be seen, that numeral 5 denotes a pot having a sloping bottom 5 anda thickened top portion 1 having a sloping inner side 8, sloping in thesame direction as the bottom 6 but at a greater angle. Upper and lowerportions of the pot 5 are of thick construction as at 9 and I and havethreaded openings for receiving the threads of an elbow I I and thethreads I2 of a trap structure generally referred to by numeral I3.

Numeral I4 denotes a mercury tube which extends to the sloping bottom 6and has entrance openings for mercury so that mercury can be forced upinto the tube by the pressure of the line being tested.

Numeral I5 denotes a slotted protector shell for the upper portion ofthe tube I4 and this has a threaded portion I6 at its lower end forthreaded disposition into the upper end of a bore I1 formed in thethickened top 1 of the pot 5, as is clearly shown in Figure 1.

The elbow I I has a short pipe section I8 extending therefrom andconnecting to a shut-off valve generally referred to by numeral I9. Thisvalve is connectible to a pipe line 20 to be tested.

The mercury trap I3 consists of a barrel 2 I, this barrel being solid atone end as at 22 and at this end formed with a threaded opening forreceiving the threaded shank 23 of a nut 24, which can be screwedagainst a graphite packing 25.

A rod 26 extends longitudinally through the barrel 2I, through the solidportion 22 and also through the nut 24. The nut 24 end of the rod 26 hasa knob 21 thereon and between this knob and the nut 24 and convoluted onthe rod 26 is a compression spring 28.

The other end of the rod 26 is provided with pot and holding the sametherein a resilient plug 29 of tapered construction and the inner end ofthis is seatable against a concaved seat 30 at the adjacent end of thebarrel 2I. It can be seen that the barrel is reduced as at 3| and hasthe threads I2 which are disposed into the thickened portion Ill of thepot 5.

In the use and operation of this gauge, and before the same is connectedto the line 20 to be tested, the gauge is tilted to a position oppositefrom that shown in Figure 3, so that by pushing inwardly on the knob 21,the valve plug 29 will be displaced and mercury previously trapped inthe barrel 2| allowed to flow into the pot 5. The knob 21 is nowreleased and the valve plug 29 returns to seated position so that themercury cannot return to the trap I3.

The shut-01f valve I9 is now connected to the line 20 and the valve I9is opened. Pressure from the line 20 will then move the mercury in thepot 5 into the column tube I4, which is of course graduated and thegraduations visible through the slot in the protector shell I5.

When the test has been completed, the gauge is disconnected from theline 20.

The gauge is now tilted to the position shown in Figure 3 and the knob21 forced inwardly. This allows the mercury to run into the trap I3 andwhen all of the mercury has come to rest in the barrel 2|, th knob 21 isreleased and the spring 28 will pull the valve plug 29 to the closedposition shown in Figure 2. The mercury is held in the trap I3 when thegauge is not in use.

While the foregoing description sets forth the invention in specificterms, it is to be understood that numerous changes in the shape, sizeand materials may be resorted to without departing from the spirit andscope of the invention as claimed hereinafter.

Having described the invention what is claimed as new is:

A mercury gauge comprising a mercury receiving pot, a gauge columnextending from the pot, a valved fitting for connection with a line tobe tested and a trap for receiving mercury from the while the gauge isnot in use, said trap being composed of an elongated barrel having oneend connected to and in communication with the pot, a rod extendinglongitudinally through the barrel, a valve element at the pot end of therod, a knob at the other end of the rod and exteriorly of the barrel anda spring on the rod at the knob end thereof for normally holding the rodmoved outwardly and the valve element engaged against the adjacent endof the barrel.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 913,010 Hohmann Feb. 23, 1909 1,027,834 Fulmer May 28, 1912

